10/17

BD1754HFN

Datasheet

TSZ02201-0G3G0C200060-1-2

10.Dec.2015 Rev.002

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TSZ22111･15･001

(3) Circuit example when the EN pin is powered ON at all times

Rs

IN

ISET

GND

Current

DAC

UPIC

6

EN

L2

L1

0.1µF

Cs

L4

L3

(When

120k

Ω

Figure 15. Circuit example when the EN Pin is Powered ON at all times

This figure shows a circuit example when the EN pin is powered ON at all times. To prevent a rush current from

occurring in the driver, it is necessary to apply voltage to the IN pin and the LEDs prior to powering the current driver

ON. Mount an RC filter between the IN and the EN pins to delay the EN pin rising against the power-supply voltage

rising. Determine the resistance value with which the LED current value is maximized and then connect such resistor

between the ISET and the GND pins.

(4) Circuit example when performing a PWM brightness control

IN

ISET

GND

Current

DAC

UPIC

6

EN

L2

L1

0.1µF

PWM

1M

Ω

120k

Ω

L4

L3

Figure 16. Circuit example when performing a PWM brightness control

This figure shows a circuit example when performing a PWM brightness control. Through switching the ISET resistance

value by the PWM input signal, the LED current is outputted under a PWM mode. The EN signal is controlled by an

applied voltage level. In the circuit example shown above, the LED current value is changed to 3.43 mA in 0 % of the

PWM duty cycle, 17.72 mA in 50 % of that and 32 mA in 100 % of that.